In 1194, Salzdetfurth was mentioned in a document for the first time. The place was devastated by fire or flood several times. The worst flood occurred in 1738 when 176 houses were destroyed. The word "Bad" meaning "spa" was added to the name in 1921. On 22 March 1945, during a heavy air raid on Hildesheim, Bad Salzderfurth was hit by several bombs and two houses in Goettingstrasse were destroyed.[2] Bad Salzdetfurth was officially awarded "town" status in 1949.

Each of the villages incorporated in 1974 has its own history and its own traditions.

There are various sights in the town itself and in each of the villages. There are many well-preserved half-timbered houses in the old town center, such as the Miners' Guild Hall dating from 1898, and in the village of Wesseln. The Catholic Church of Saint Gallus at Detfurth was built in a classicist style in the period 1772 to 1779. Other interesting village churches and chapels can be seen in Hockeln, Bodenburg, Breinum, Östrum, Wehrstedt and Klein Düngen. The Church of Saint John the Baptist in Wesseln was built in a typical neogothic style in 1853-55.

The largest church in Bad Salzdetfurth itself is St. George's Church, a Protestant church with a painted wooden ceiling, which was built around 1700. In the west wall a mark, which is 3 meters above ground level, indicates the height of the flood waters of the River Lamme in 1738. The baroque altar dates from 1717. The organ, dating from 1590, originally stood in St. Lamberti, Hildesheim. There is a municipal museum dedicated to the mining history of Bad Salzdetfurth. Originally the brick building which now houses the museum was a school. The museum was founded in 1987.

The most modern church in Bad Salzdetfurth is the Catholic Holy Family Church which was built 1960-61 and consecrated on 3 September 1961. Its organ dates from 1979. Originally, very few Catholics lived in Bad Salzdetfurth. After World War II, however, many Catholic refugees from Silesia settled in the town.

Bad Salzdetfurth can be reached from Hildesheim by train. The railway station is in the middle of the town. There are railway halting places in the villages Bodenburg, Detfurth, Wesseln and Groß Düngen as well. On working days, there is at least one train per hour to and from Hildesheim. On Sundays and public holidays there is one train every two hours.